Diaminotetrafluoroethoxybenzenes, process for producing same and hair coloring agents containing same

ABSTRACT

Tetrafluoroethoxybenzenes, and their acid addition salts, of the general formula: ##STR1## in which R 1  may represent hydrogen or an alkyl having from 1 to 4 carbon atoms and R 2 , R 3  and R 4  represent one or more of the same or different substituents selected from hydrogen, an alkyl having 1 to 4 carbon atoms or mono- or dihydroxyalkyls having 1 to 4 carbon atoms, provided that the amino groups are situated relative to one another in an ortho- or meta- position and R 1 , R 2 , R 3  and R 4  do not simultaneously represent hydrogen when the amino groups are arranged in a 2,4-position. The compounds of the invention, along with 2,4-diaminotetrafluoroethoxybenzene, are useful as coupler components in oxidative hair coloring agents. A process for making the compounds, as well as a separate process for making the mono-N-β-hydroxyethyl compounds, is provided.

This application is a continuation of application Ser. No. 758,203,filed July 22, 1985 now abandoned.

The present invention relates to new diaminobenzene derivativescontaining a tetrafluoroethoxy group, their preparation and applicationas components of agents for the oxidative coloring of hair in whichknown developing components are employed along withdiaminotetrafluoroethoxybenzenes as coupling components.

Oxidizing coloring materials are known to be of substantial importancein the coloring of hair. The coloring is effected by means of thereaction of certain developer substances with certain coupler substancesin the presence of a suitable oxidizing agent.

The preferred coupler substances currently being used arem-phenylenediamine and its derivatives, e.g., 2,4-diaminoanisol,2,4-diaminophenetol and 2-amino-4-(β-hydroxyethyl)aminoanisol as bluecouplers: α-napthol, m-aminophenol and 5-amino-o-cresol as red couplers;and resorcinol, 2-methylresorcinol and 4-chlororesorcinol as couplersfor the brown-blond range.

The preferred developer substances being used are, e.g.,2,5-diaminotoluene, 4-aminophenol and 1,4-diaminobenzene, however,2,5-diaminoanisol, 2,5-diaminobenzyl alcohol and2-(β-hydroxyethyl)-1,4-diaminobenzene have also achieved a certainimportance. In certain cases, tetraaminopyrimidine can also be used as adeveloper substance.

There are numerous special requirements that oxidizing coloringmaterials which are used for coloring human hair must meet. They must,for example, be generally recognized as safe in toxicological anddermatological respects and must make it possible to achieve coloring tothe desired intensity. Moreover, it is a requirement that a wide rangeof various nuances of color be able to be produced by means of combiningsuitable developer and coupler substances. In addition, the attainablehair colorings are required to be favorably light fast, permanent wavefast, acid fast and friction fast. However, in all instances such haircolorings must also remain stable over a period of at least four to sixweeks without being affected by light, chemical agents or friction.

While the system comprising the aforesaid developer and couplersubstances, which is currently being used in hair coloring agents, meetsthe stated requirements in terms of those features relating toapplication technology, it does not satisfy the demands relating totoxicity. Furthermore, it is also desirable that compounds used in haircoloring systems not be mutagenic, or only slightly mutagenic, incommercially known testing methods such as those of B. N. Ames.

Accordingly, it is an object of the present invention to provide haircoloring agents based upon new coupler substances which, inter alia,allow for a wide range of various nuances of colorings that are stablefor an extended period of time without being adversely affected bylight, chemical agents and friction and which have a high toxicologicallevel of safety.

This and other related objects are achieved according to the compoundsof the present invention. In particular, it has been found, verysurprisingly, that the toxicological characteristics of certain couplingcomponents conventionally applied in oxidizing hair coloring agents canbe substantially improved by means of introducing the tetrafluoroethoxygroup into these compounds.

The present invention, therefore, provides agents for the oxidativecoloring of hair having a combination of developer and couplersubstances in which such agents contain, as the coupler substance, adiaminotetrafluoroethoxybenzene compound, or its acid addition salt, ofthe general formula I. ##STR2## wherein,

R¹ represents hydrogen or an alkyl group having 1 to 4 carbon atoms; and

R², R³, and R⁴ independently of one another, represent hydrogen, analkyl group having 1 to 4 carbon atoms or mono- or dihydroxy alkylgroups having 1 to 4 carbon atoms, provided that the amino groups aresituated relative to one another in an ortho- or meta-position.

The coupler substances of the present invention, having physiologicallyfavorable characteristics, above all, have a lower level of mutagenicitythan structurally similar non-fluorinated compounds. Moreover, theimprovement demonstrated by the compounds of the present inventionrelative to the corresponding trifluoroethoxy compounds is alsoparticularly surprising and unexpected.

In addition, a comparison, described below, of the coupler substances ofthe present invention, in which R¹ is an alkyl group, shows a distinctimprovement of the light fastness for those compounds alkylated in thenucleus relative to those compounds wherein R¹ is a hydrogen atom. Thelight fastness can likewise be improved by substituting the nitrogenatom. Those compounds of formula I in which at least one of thesubstituents designated R¹ to R⁴ is an alkyl or hydroxy alkyl group are,therefore, particularly well-suited for use in the hair coloring agentsaccording to the invention. The substituents methyl and hydroxyethylbeing particularly preferred. With respect to the positioning of theamino groups, those compounds in which the amino groups are in ameta-position relative to one another are preferred.

The following table shows the results of the mutagenicity test accordingto B. N. Ames (B. N. Ames, J. MacCann and E. Yamasaki, Mut. Res. 31347-363 (1975)) for two of the coupler substances of formula I incomparison to the known coupler substances,2,4-diaminotrifluoroethoxybenzene, 2,4-diaminophenetol and2,4-diaminoanisol.

                  TABLE                                                           ______________________________________                                        Ames test results of 2,4-diaminoalkoxy benzene derivatives                                Salmonella thyphimurium strains                                               without (-) and with (+) S9 - Mix                                             TA 97   TA 98    TA 100                                           Substance     -      +      -   +    -    +                                   ______________________________________                                        2,4-diamino-5-                                                                              -      -      -   -    -    -                                   tetrafluoroethoxy-                                                            toluene                                                                       2,4-diaminotetra-                                                                           -      (+)    -   +    -    -                                   fluoroethoxy-                                                                 benzene                                                                       2,4-diaminotri-                                                               fluoroethoxy- -      -      -   ++   -    (+)                                 benzene                                                                       2,4-diaminophenetol                                                                         -      +      -   ++   -    -                                   2,4-diaminoanisol                                                                           -      +      -   30 + -    (+)                                 ______________________________________                                         no back mutation:                                                             slight back mutuation: (+)                                                    increasing back mutation: +, +                                           

The coupler substances of formula I are new, with the exception of thecompound 2,4-diaminotetrafluoroethoxybenzene which is described in theRussian Pat. No. 537 504 as a starting compound for the production ofpolyamides.

Thus, the present invention also relates to newdiaminotetrafluoroethoxybenzene compounds, and their acid additionsalts, of general formula I, wherein, R¹ represents hydrogen or an alkylgroup having 1 to 4 carbon atoms and R², R³ and R⁴ represent,independently of one another, hydrogen, an alkyl group having 1 to 4carbon atoms or mono- or dihydroxy alkyl groups having 1 to 4 carbonatoms, provided that the amino groups are situated relative to oneanother in an ortho- or meta-position, and R¹ through R⁴ do notsimultaneously signify hydrogen when the amino groups are arranged in a2,4-position.

Processes for the production of several of the inventivediaminotetrafluoroethoxy couplers is described in the following exampleswhich are presented solely for purposes of illustration and not oflimitation. In general, the compounds alkylated at the nitrogen atomwere produced by dinitrating the compounds of general formula II,##STR3## wherein, R¹ stands for hydrogen or an alkyl group having 1 to 4carbon atoms, followed by the subsequent reduction of the dinitrocompound III. The reduction can be carried out catalytically withhydrogen or with inorganic reducing agents. ##STR4##

In order to produce the dinitro compounds one can also, of course, startfrom the mononitro aromatics occurring in the mononitration of II.

The dinitro compounds, III, can serve as starting material for thederivatives alkylated at the nitrogen atom. The careful reduction of anitro group, e.g., with ascorbic acid or ammonium polysulfide, producesthe nitroaniline derivative IV which is also accessible from II by meansof mononitration, reduction and a second nitration. Further reaction ofthe nitroaniline derivative IV by means of alkylation and reductionproduces the derivatives of the compounds according to formula I whichare alkylated at the nitrogen atom. ##STR5##

A special method for producing the mono-N-β-hydroxyethyl compoundsresults from the mononitro compounds produced in the nitration of II,its reduction, reaction with chloroformic acid chloroethylester andsubsequent nitration, reduction and dissociation of the oxazolinonaccording to the following reaction scheme: ##STR6##

In addition, the compounds alkylated at the nitrogen atom can also beproduced from the free amines, in a known manner by means of alkylation,by applying conventional N-alkylation methods as illustrated in thefollowing examples.

The acid addition salts of the compounds of formula I are obtainable bymeans of reaction with the corresponding organic or inorganic acids.

The coupler substances of formula I are to be used in hair coloringagents in either a free base form or in the form of theirphysiologically compatible salts with inorganic or organic acids, e.g.,as chlorides, sulfates, phosphates, acetates, propionates, lactates orcitrates. The compounds of formula I are easily soluble in water and,moreover, have an excellent storage stability, particularly as acomponent part of the hair coloring agents described herein.

In the hair coloring agents, the coupler substances of formula I are tobe contained in a concentration of 0.01 to 3.0% by weight, preferably,0.1 to 2.0% by weight.

While the coupler substances of formula I are generally employed inapproximately equimolar quantities with reference to the developersubstances used, it is not disadvantageous if the coupler substances areapplied with a certain excess or deficiency. It is also not necessarythat the developer components and the coupler components each behomogeneous compounds; rather, the developer components can be a mixtureof known developer substances while the coupler components can be amixture of the compounds according to the present invention and knowncoupler substances. Examples of known coupler substances that can becontained in the hair coloring agents include, in particular,resorcinol, 4-chlororesorcinol, 2-methylresorcinol,2-amino-4-(β-hydroxyethylamino)-anisol, 2,4-diamino-phenylethanol,2,4-diamino-phenoxyethanol, 1,5-dihydroxytetraline, m-aminophenol,3-amino-2-methylphenol, 3-amino-6-methylphenol,4-hydroxyl-1,2-methylenedioxybenzene, 4-amino-1,2-methylenedioxybenzene,2,4-diaminoanisol and 2,4-diaminophenetol.

Of the known developer substances mainly 1,4-diaminobenzene,2,5-diaminotoluene, 2,5-diaminoanisol, 2,5-diaminobenzyl alcohol,3-methyl-4-aminophenol and 4-aminophenol come under consideration ascomponent parts in the hair coloring agents of the present invention.

The total quantity of the developer substance-coupler substancecombination contained in the hair coloring agents described hereinshould amount to approximately 0.1 to 5.0% by weight, preferably 0.5 to3.0% by weight, of the hair coloring agents of the present invention.

In addition, in order to achieve certain color nuances conventionaldirect dyeing coloring materials can also be contained, e.g.,triphenylmethane dyes, such as, Diamond Fuchsine (C.I. 42,510) andLeather Ruby HF (C.I. 42,520); aromatic nitro dyes, such as2-amino-4,6-dinitrophenol, 2-nitro-1,4-diaminobenzene,2-amino-4-nitrophenol and 2-amino-5-nitrophenol; and azo dyes, such as,Acid Brown 4 (C.I. 14,805), as well as anthraquinone dyes such as1,4-diaminoanthraquinone.

In addition, the claimed hair coloring agents can also containself-coupling preliminary coloring stages, such as, e.g.,2-amino-5-methylphenol, 2-amino-6-methylphenol, 2-amino-5-ethoxyphenolor 2-propylamino-5-aminopyridine.

Of course, the coupler and developer substances, as well as othercoloring components, insofar as they are bases, can be used in the formof physiologically compatible acid addition salts, for example, ashydrochlorides or sulfates or--insofar as they possess aromatic OHgroups--in the form of salts with bases, for example, as alkaliphenates.

Moreover, other conventional cosmetic additives can be present in thehair coloring agents, for example, antioxidants such as ascorbic acid orsodium sulfite, perfume oils, complexing agents, wetting agents,emulsifiers, thickeners, conditioning materials, etc.

The preparation form can be, e.g., a solution, particularly an aqueousor aqueous alcohol solution. However, particularly preferred preparationforms are creams, gels or emulsions.

The composition of the hair coloring agents is a mixture of coloringmaterial components with the usual additives for such preparations.

Conventional additives in solutions, creams, emulsions or gels are, forexample, solvents such as water, lower aliphatic alcohols, e.g.,ethanol, propanol and isopropanol, as well as polyhydric alcohols suchas ethylene glycol, 1,2-propylene glycol and glycerin, in addition towetting agents or emulsifiers of the classes of anionic, cationic,amphoteric or non-ionogenic surface-active substances such as fattyalcohol sulfates, alkylsulfonates, alkylbenzenesulfonates,alkyltrimethylammonium salts, alkylbetaines, ethoxylated fatty alcohols,ethoxylated nonylphenols, fatty acid alkanolamides, ethoxylated fattyacid esters, and thickeners, such as, higher fatty alcohols, bentonite,starch, polyacrylic acid, cellulose derivatives, alginates, Vaseline,paraffin oil and fatty acids, as well as conditioning materials such aslanolin derivatives, cholesterol, pantothenic acid and betaine. Thesecomponent parts are used in quantities usual for such purposes, forexample, the wetting agents and emulsifiers can be contained inconcentrations of approximately 0.5 to 30% by weight, while thethickeners can be contained in the preparation in quantities ofapproximately 0.1 to 25% by weight.

Depending on the particular composition, the hair coloring agents of theinvention can react in a slightly acidic, neutral or alkaline manner. Inparticular, they have a pH value in the alkaline range of 8.0 to 11.5,wherein adjustment is preferably effected with ammonia. But organicamines, for example, monoethanolamine and triethanolamine, or inorganicbases, e.g., sodium hydroxide and potassium hydroxide, can also be used.

For application in the oxidative coloring of hair the above-mentionedhair coloring agents are mixed immediately before use with an oxidizingagent and an amount of the mixture sufficient for the hair coloringtreatment, generally in the range of approximately 60 to 200 g,depending on the quantity of hair, is applied to the hair.

Hydrogen peroxide, in particular, is taken into consideration as anoxidizing agent for developing the hair coloring, for example, as a 6%aqueous solution or its addition compounds in urea, melamine or sodiumborate. The mixture is then allowed to act on the hair at 15° to 50° C.for approximately 10 to 45 minutes, preferably 30 minutes. The hair isthen immediately rinsed with water and dried. After rinsing, the hair ispossibly washed with a shampoo and rerinsed with a weak, physiologicallycompatible organic acid, e.g., citric acid or tartaric acid.

With respect to the coloring possibilities, the hair coloring agents,according to the invention, offer a wide selection of various colornuances, dependent upon the type and composition of the coloringcomponents employed. The colorings may range from blonde, brown, ash,mat, and golden to blue color tones. The color tones are characterizedby a good intensity of color and sufficient light fastness.

Finally, it is also possible, with the aid of the hair coloring agentsemploying the present invention, to tint graying, chemically undamagedhair with good covering power.

The invention will now be more fully described by the followingexamples. It should, however, be noted that such are given by way ofillustration and not of limitation. Unless otherwise indicated, allpercentages in the following Examples represent percentages by weight.

PRODUCTION EXAMPLES Example 1: 2,4-diaminotetrafluoroethoxybenzene Step1: 2,4-dinitrotetrafluoroethoxybenzene production

6 g (0.025 moles) of 2-nitrotetrafluoroethoxybenzene or4-nitrotetrafluoroethoxybenzene are dissolved in 20 ml concentratedsulfuric acid (density, d=1.84 g/ml) and nitrated at 5°-10° C. with amixture of 1.2 ml nitric acid (d=1.5 g/ml) and 5 ml sulfuric acid(d=1.84 g/ml). After the addition of the nitrating acid, the aforesaidpreparation is allowed to heat at room temperature. The preparation,after being left to stand overnight, is then poured onto ice water. Theprecipitated oil is separated by means of decanting and the aqueousphase is extracted three times with 50 ml ether. The ether extracts andthe oil are then combined, washed with sodium bicarbonate solution so asto be acid-free and dried over calcium chloride. After distilling thesolvent, 6.6 g (93% of the theoretical yield) dinitro compound (from the2-nitrotetrafluoroethoxybenzene) or 6.7 g (94% of the theoretical yield)dinitrotetrafluoroethoxybenzene (from the4-nitrotetrafluoroethoxybenzene) is obtained. The dinitro compound wasfurther processed directly in the following step without furtherpurification.

Step 2: 2,4-diaminotetrafluoroethoxybenzene production

89 g (0.31 moles) 2,4-dinitrotetrafluoroethoxybenzene, according to Step1, 125 ml of a 50% aqueous solution of ethanol and 106.5 g iron powder(1.91 moles) are heated to 60°-70° C. in a water bath in a three-neckedflask, which is equipped with a reflux condensor, drop addition funnel,stirrer and internal thermometer. Next, a solution of 6.5 mlconcentrated hydrochloric acid in 30 ml 50% aqueous solution of ethanolis added dropwise so that the reduction takes place accompanied byreflux and gentle boiling. When the addition is terminated it is thenstirred for 2 hours accompanied by reflux, allowed to cool andneutralized with alcoholic potassium hydroxide. Unconverted iron andiron oxides are vacuum filtrated, accompanied by rewashing with ethanol.The solution is concentrated and the residue is distilled in the vacuum.40 g (57% of the theoretical yield) of the free base is obtained whichhas a boiling range of 114°-117° C. at 106 Pascal. This product can betransformed into dihyrochloride with hydrochloric acid.

    ______________________________________                                        ANALYSIS (dihydrochloride)                                                                calculated                                                                            found                                                     ______________________________________                                        C             32.34%    32.78%                                                H             3.39%     3.41%                                                 N             9.42%     9.78%                                                 Cl            23.86%    24.16%                                                ______________________________________                                    

Example 2: 2,4-bis-[(2'-hydroxylethyl)-amino]-tetrafluoroethoxybenzeneStep 1: 2,4-bis-(2'-chloroethoxycarbamido)-tetrafluoroethoxybenzeneproduction

2.47 g (8.3 mmoles) 2,4-diaminotetrafluoroethoxybenzenedihydrochlorideof Example 1 are dissolved in 10 ml dioxane and heated for 1 hour to 90°C. with 2 g calcium carbonate and 4.3 g (30 mmoles) chloroformic acidchloroethylester.

This mixture is then poured onto ice with the residue being filteredoff, dried and then used without further purification in Step 2.

Step 2: 2,4-bis-[(2'-hydroxylethyl)-amino]-tetrafluoroethoxybenzeneproduction

3.5 g (8.0 mmoles) of the dicarbamates from Step 1 are heated in 20 ml20% aqueous sodium hydroxide solution for 1 hour to 120° C. (bathtemperature), cooled, then extracted with ethyl acetate. The combinedethyl acetate phases are washed once with water and dried over sodiumsulfate. The solvent is then evaporated in a vacuum with the residuebeing transformed into dihydrochloride. The dihydrochloride, with amelting point of 145° C., be recrystalized from methyl ethyl ketone.

    ______________________________________                                        ANALYSIS        calculated                                                                              found                                               ______________________________________                                        C               37.41%    37.87%                                              H               4.71%     4.81%                                               N               7.27%     7.34%                                               Cl              18.40%    17.94%                                              ______________________________________                                    

For all of the following NMR spectrums: All data in δ [ppm] Standard:tetramethylsilane s=singlet, d=doublet, t=triplet, m=multiplet

NMR spectrum (in DMSO-d₆);

8.2-7.4 (wide, NH₃.sup.⊕, OH, when the sample is agitated with D₂ O thesignal disappears), 7.27 (d, J=8 Hz, 6-H), 7.12 (t, J=52 Hz, threesignals at 7.64, 7.12 and 6.60 ppm again form triplets with J=4 Hz, CF₂CHF₂), 7.04 (d, J=2 Hz, 3-H), 6.83 (dd, J₁ =8 Hz, J₂ =2 Hz, 5-H),3.8-3.5 (m, --CH₂ OH), 3.5-3.1 (m, --CH₂ NH--).

Example 3: 3,4-diaminotetrafluoroethoxybenzene Step 1:4-acetylaminotetrafluoroethoxybenzene production

23.9 g (0.1 moles) 4-nitrotetrafluoroethoxybenzene are dissolved in 75ml glacial acetic acid and reduced at 50°-60° C. in the presence ofplatinum with hydrogen at normal pressure. After receiving 7.4 1hydrogen the catalyst was filtered off and the filtrate is heated 1 hourwith 75 ml acetic anhydride accompanied by reflux. The reaction mixtureis then concentrated in a vacuum to 1/3 the original solvent quantityand poured onto 1 l ice water. The acetyl amino compound firstprecipitates as an oil which crystalizes overnight. 23.5 g (94%theoretical yield) of almost colorless crystals with a melting range of114°-115° C. are obtained.

Step 2: 4-amino-3-nitrotetrafluoroethoxybenzene production

18.8 g (0.08 moles) 4-acetylaminotetrafluoroethoxybenzene of Step 1 aredissolved, accompanied by ice cooling at 0° C., in 150 ml concentratedsulfuric acid. Nitration is carried out at the same temperature with amixture of 10.3 ml (0.15 moles) concentrated nitric acid (d=1.4 g/ml)and 10 ml concentrated sulfuric acid. After standing overnight thismixture is poured onto approximately 500 g ice. A viscous oilprecipitates. The oily phase is decanted and repeatedly washed withwater. The oil is made to solidify by means of cooling and scraping. Itis, according to DC, a mixture of acetylaminonitro- andaminonitro-compounds. It is then saponfied by means of dissolving andboiling, with reflux, with methanol and concentrated hydrochloric acidand then neutralized with ammonia. The4-amino-3-nitrotetrafluoroethoxybenzene precipitates. Yellow crystalswith a melting point of 78° C. were obtained. Yield: 13.4 g (67% of thetheoretical yield)

Step 3: 3,4-diaminotetrafluoroethoxybenzene production

12.7 g (0.05 moles) 4-amino-3-nitrotetrafluoroethoxybenzene from Step 2is dissolved in 100 ml ethanol and catalytically reduced in the presenceof platinum at 50° C. with hydrogen at normal pressure. After receiving3.6 l hydrogen, the catalyst is filtered off and 10 ml concentratedhydrochloric acid is added to the alcoholic solution. It is steamed dryand completely dried in the vacuum dessicator over potassium hydroxide.Yield: 12.5 g (84.5% of the theoretical yield) of3,4-diaminotetrafluoroethoxybenzene dihydrochloride. The resultingsubstance is in the form of red-brown crystals which are recrystalizedfrom ethanol/HCl. Melting (decomposition) range 198°-200° C. HCLcontent, potentiometrically determined: 23.80%. Calculated value:24.57%.

Example 4: 3-amino-4-(2'-hydroxylethyl)-aminotetrafluoroethoxybenzeneStep 1: 2-chloroethyl-N-(4'-tetrafluoroethoxyphenyl)carbamate production

41.8 g (0.20 moles) 4-aminotetrafluoroethoxybenzene (obtained from theprocess disclosed in Example 3, Step 1, without acetylation step) isdissolved in 100 ml dioxane. 12.0 g calcium carbonate and 31.4 g (0.22moles) chloroformic acid chloroethylester are added and heated for 30minutes to 90° C. This mixture is then poured onto ice with the residuebeing filtered off and recrystalized from methanol/water. Colorlesscrystals having a melting range of 114°-116° C. were obtained in almosta quantitative yield.

Step 2:

N-(4'-tetrafluoroethoxyphenyl)-oxazolidin-2-on 62.0 g (0.20 moles) ofthe carbamate from the first step of this Example is heated for 1 hourin 200 ml 1N sodium hydroxide solution (0.20 moles NaOH). When cooling,a precipitation results which is recrystalized from methanol/water. Theoxazolidinon crystalizes in colorless crystals having a melting range of74°-76° C.

Step 3: N-(2'-nitro-4'-tetrafluoroethoxyphenyl)-oxazolidin-2-onproduction

2.79 g (10 mmoles) of the oxazolidinon of Step 2 are dissolved in 7 mlconcentrated sulfuric acid and nitrated at 0° C. with a mixture of 0.43ml (10 mmoles) fuming nitric acid and 3.6 ml concentrated sulfuric acid.

The preparation is then poured onto ice so that an oil precipitateswhich crystalizes within a short time. Slightly yellowish crystals areobtained having a melting point of 83° C.

Step 4: N-(2'-amino-4'-tetrafluoroethoxyphenyl)-oxazolidin-2-onproduction

The reduction of the nitro compound of Step 3 is carried outcatalytically in the presence of platinum with hydrogen at normalpressure. Acetic acid is used as a solvent. After receiving thetheoretical hydrogen quantity, the catalyst is filtered off and thesolvent is evaporated with a vacuum. The amino compound is obtained inquantitative yield as colorless crystals of melting range 106°-108° C.

Step 5:

The oxazolidinon of Step 4 is dissociated in 20% aqueous sodiumhydroxide solution as described in the second step of Example 2. Thedihydrochloride, with a melting point of 118° C., is obtained incolorless crystals.

Example 5: 2,4-diamino-3-tetrafluoroethoxytoluene and2,4-diamino-5-tetrafluoroethoxytoluene Step 1:4-nitro-3-tetrafluoroethoxytoluene production

20.8 g (0.10 moles) 3-tetrafluoroethoxytoluene is placed in 25 mlglacial acetic acid and nitrated at 5° C. with a mixture of 30 mlconcentrated nitric acid and 35 ml concentrated sulfuric acid. Thesolution turns yellow as the nitrating acid is added dropwise. When theaddition is terminated the cooling bath is removed and the solution isagitated for 31/2 hours at room temperature. The solution is then pouredonto ice, the precipitated oil separated and the aqueous solution isextracted with ethyl acetate. After drying over sodium sulfate anddistilling the solvent, a yellow oil remains in quantitative yield,which according to the NMR spectrum, involves the4-nitro-3-tetrafluoroethoxytoluene.

NMR (solvent: CDCl₃): 8.06 (d, J=10 Hz, 5-H), 7.4-7.1 (m, 2-H and 6-H),5.93 (t, J=53 Hz, the three signals at 6.82, 5.93, 5.04 again formtriplets with J=3 Hz, CF₂ CHF₂), 2.65 (s, CH₃)

Step 2: 2,4-dinitro-5-tetrafluoroethoxytoluene and2,4-dinitro-3-tetrafluoroethoxytoluene production

5.1 g (0.02 moles) of the mononitro compound from Step 1 are dissolvedin 5 ml concentrated sulfuric acid and nitrated at 0°-5° C. with amixture of 7.5 ml fuming nitric acid (d=1.50 g/ml) and 9 ml concentratedsulfuric acid. After adding the nitrating acid, which takesapproximately 40 minutes, the ice bath is removed and the preparation isagitated for 24 hours at room temperature. This preparation is thenpoured onto ice, the precipitated oil is separated immediately and theaqueous phase is extracted with ethyl acetate. After combining theorganic phases, the latter are dried over sodium sulfate and the solventevaporated in a vacuum. 5.4 g (90% of the theoretical yield) of amixture of the two dinitro compounds is obtained which is separated bymeans of column chromatography (SiO₂,<0.063 mm, eluent: cyclohexane/2%ether).

The two compounds, 2,4-dinitro-3-tetrafluoroethoxytoluene and2,4-dinitro-5-tetrafluoroethoxytoluene are present in a ratio of 1:3,the 3-tetrafluoroethoxy compound has the higher R_(F) value. The twodinitro compounds are oils in the pure state.

NMR spectrum of the 2,4-dinitro-3-tetrafluoroethoxytoluene (dissolved inCDCl₃): 8.16 (d, J=9 Hz, 5-H), 7.52 (d, J=9 Hz, 6-H, signals widen bycoupling with CH₃), 5.93 (t, J=53 Hz, the three signals at 6.81, 5.93and 5.05 ppm again form triplets with J=3 Hz, CF₂ CHF₂), 2.60 (s, CH₃).

NMR spectrum of the 2,4-dinitro-5-tetrafluoroethoxytoluene (dissolved inCDCl₃): 8.74 (s, 3-H), 7.52 (s, 6-H, widens by coupling with CH₃), 6.05(t, J=53 Hz, the three signals at 6.92, 6.05 and 5.17 ppm again formtriplets with J=4 Hz, CF₂ CHF₂), 2.81 (s, CH₃).

Step 3(a): 2,4-diamino-3-tetrafluoroethoxytoluene production

0.2 g (0.7 mmoles) 2,4-dinitrotetrafluoroethoxytoluene is hydrogenatedin 10 ml ethanol with hydrogen at normal pressure in the presence ofplatinum. After receiving 90 ml hydrogen (theoretical yield: 94 ml) thecatalyst is filtered off and the dihydrochloride is produced with HCl.Reddish crystals having a melting (decomposition) point of 180° C. areobtained.

NMR spectrum (in DMSO-d₆): 7.2 (m, 5-H, 6-H), 7.2-6.6 (wide, NH₃.sup.⊕,the signal disappears when agitated with D₂ O), 6.66 (t, J=51 Hz, CF₂CHF₂ ; further splitting in triplets of the three signals at 7.50, 6.66and 5.82 ppm cannot be detected because of strong background noise),2.10 (s, CH₃).

Step 3(b): 2,4-diamino-5-tetrafluoroethoxytoluene production

0.5 g (2 mmoles) 2,4-dinitro-5-tetrafluoroethoxytoluene is hydrogenatedin 15 ml ethanol with hydrogen at normal pressure with platinum as acatalyst. After receiving 250 ml hydrogen (theoretical: 268 ml) thecatalyst is filtered off and the dihydrochloride is produced withhydrochloric acid. Almost colorless crystals with a melting range of265°-267° C. are obtained (decomposition; in closed tube).

NMR spectrum (in DMSO-d₆): 8.35 (wide, NH₃.sup.⊕, the signal disappearswhen agitated with D₂ O), 7.12 (s, 3-H, 6-H) 6.90 (t, J=53 Hz, the threesignals at 7.79, 6.90 and 6.01 ppm again form triplets with J=4 Hz, CF₂CHF₂), 2.25 (s, CH₃).

Example 6: 3,5-diamino-2-tetrafluoroethoxytoluene and4,5-diamino-2-tetrafluoroethoxytoluene Step 1:3,5-dinitro-2-tetrafluoroethoxytoluene and4,5-dinitro-2-tetrafluoroethoxytoluene production

2.5 g (10 mmoles) 5nitro-2-tetrafluoroethoxytoluene is added dropwise toa solution of 1.5 g (14.8 mmoles) potassium nitrate in 15 mlconcentrated sulfuric acid at room temperature accompanied by agitation.The solution is then heated for 3 hours to 100° C. After cooling, it ispoured onto ice and extracted with ethyl acetate. The combined organicphases are washed with water and sodium carbonate solution and driedover sodium sulfate. After distilling the solvent an oil remains which,aside from the two desired nitro compounds, contains a little phenolicby-product. Separation occurs by means of filtration via a short silicagel column (eluent: toluene). The filtrate is concentrated in a vacuumand the residue is analyzed chromatographically with silica gel (<0.063mm, eluent: cyclohexane/2% ether).

The 3,5-dinitro-2-tetrafluoroethoxytoluene and the4,5-dinitro-2-tetrafluoroethoxytoluene are obtained in a ratio of 5:4,the m-nitro compound appears first in the column chromatography.

NMR spectrum of the 3,5-dinitro-2-tetrafluoroethoxytoluene (dissolved inCDCl₃): 8.66 (d, J=3 Hz, 4-H), 8.45 (d, J=3 Hz, 6-H), 6.07 (t, J=53 Hz,the signals at 6.95, 6.07 and 5.19 ppm again form triplets with J=3.5Hz, CF₂ CHF₂), 2.61 (s, CH₃).

NMR spectrum of the 4,5-dinitro-2-tetrafluoroethoxytoluene (dissolved inCDCl₃): 7.88 (s, 3-H, 6-H), 6.02 (t, J=53 Hz, the signals at 6.90, 6.02and 5.14 ppm again form triplets with J=2.5 Hz, CH₂ CHF₂), 2.50 (s,CH₃).

Step 2(a): 3,5-diamino-2-tetrafluoroethoxytoluene production

0.5 g (1.7 mmoles) of the 3,5-dinitro-2-tetrafluoroethoxytoluene ishydrogenated in ethanol with platinum as described in Example 5, Step3(b). The dihydrochloride is obtained in the form of reddish crystalswith a melting (decomposition) point of 241° C.

NMR spectrum (in DMSO-d₆): 8.5 (wide, NH₃.sup.⊕l , the signal disappearswhen agitated with D₂ O), 6.91 (t, J=53 Hz, the signals at 7.80, 6.91and 6.02 ppm again form triplets with J=4 Hz, CF₂ CHF₂), 6.76 and 6.51(both d, J=3 Hz, 4-H and 6-H, respectively), 2.20 (s, CH₃).

Step 2(b): 4,5-diamino-2-tetrafluoroethoxytoluene production

0.4 g (1.3 mmoles) of the 4,5-dinitro-2-tetrafluoroethoxytoluene ishydrogenated as in Step 2(a). Greenish crystals of dihydrochloride areobtained having a melting (decomposition) point of 238° C.

NMR spectrum (in DMSO-d₆): 8.9 (N.sup.⊕ H₃, the signal disappears whenagitated with D₂ O), 7.07 and 7.01 (2 wide singlets, 3-H and 6-H,respectively). 6.82 (t, J=53 Hz, the three signals at 7.70, 6.82 and5.94 again form triplets with J=3 Hz, CF₂ CHF₂, 2.10 (s, CH₃).

Example 7: 2,3-diamino-4-tetrafluoroethoxytoluene Step 1:3-nitro-4-tetrafluoroethoxytoluene production

2.1 g (10 mmoles) 4-tetrafluoroethoxytoluene is placed in 5 mlconcentrated sulfuric acid. A solution of 1.01 g (10 mmoles) potassiumnitrate in 25 ml concentrated sulfuric acid added to this solutiondropwise at 10° C. within 11/2 hours and then poured onto ice andextracted with ethyl acetate. The combined organic phases are washedwith water, dried over sodium sulfate and the solvent is evaporated inthe vacuum. 2.0 g (78% of the theoretical yield) of the mononitrocompound is obtained in the form of an almost colorless oil.

NMR spectrum (in CDCl₃): 7.85 (s, wide, 2-H), 7.38 and 7.36 (2 singlets,5-H and 6-H, respectively) 5.90 (t, J=53 Hz, the three signals at 6.78,5.90 and 5.02 ppm again form triplets with J=3 Hz, CF₂ CHF₂), 2.62 (s,CH₃).

Step 2: 2,3-dinitro-4-tetrafluoroethoxytoluene production

1.5 g (5.9 mmoles) 3-nitro-4-tetrafluoroethoxytoluene is placed in 7.5ml concentrated sulfuric acid and 0.65 g (6.4 mmoles) potassium nitratein 3 ml concentrated sulfuric acid is added dropwise at 0° C. After theaddition is terminated it is agitated for 2 hours at ice bathtemperature and then poured onto ice. The dinitro compound precipitatesas an oil and is extracted with ether. The combined ether phases arewashed with sodium bicarbonate solution and water and dried over sodiumsulfate. When the solvent is distilled the2,3-dinitro-4-tetrafluoroethoxytoluene remains as a yellow oil whichcrystalizes after standing for a short time. Yield: 1.55 g (88% of thetheoretical yield), melting point: 35° C.

NMR spectrum (in CDCl₃): 7.66 (s, 5-H and 6-H), 5.94 (t, J=53 Hz, thethree signals at 6.84, 5.94 and 5.04 ppm again form triplets with J=3Hz, CF₂ CHF₂), 2.52 (s, CH₃).

Step 3: 2,3-diamino-4-tetrafluoroethoxytoluene production

1.55 g (5.2 mmoles) of the 2,3-dinitro-4-tetrafluoroethoxytoluene ishydrogenated at room temperature and normal pressure with platinum as acatalyst in 20 ml glacial acetic acid with hydrogen. After receiving 740ml hydrogen (theoretical yield: 750 ml) the catalyst is filtered off andthe glacial acetic acid is evaporated with a vacuum. The free base istransformed into dihydrochloride in ether with hydrochloric acid. 0.70 g(43% of the theoretical yield) colorless crystals are obtained with amelting range of 153°-154° C.

NMR spectrum (in DMSO-d₆): 7.8 (wide, NH₃.sup.⊕, the signal disappearswhen the sample is agitated with D₂ O), 6.96 (d, J=9 Hz, 5-H and 6-H,respectively), 6.90 (t, J=53 Hz, the three signals at 7.43, 6.90 and6.37 ppm again form triplets with J=4 Hz, CF₂ CHF₂), 2.25 (s, CH₃), 6.65(d, J=9 Hz, 5-H and 6-H, respectively).

EXAMPLES OF HAIR COLORING AGENTS Example 8: Hair coloring agent in gelform

    ______________________________________                                        1.00 g        2,4-diaminotetrafluoroethoxybenzene-dihydro-                                  chloride produced according to Example 1                        0.75 g        2,5-diaminotoluene sulfate                                      0.30 g        ascorbic acid                                                   1.00 g        hydroxylethyl cellulose, highly viscous                         5.00 g        lauryl alcohol diglycolethersulfate, sodium salt                              (28% aqueous solution)                                          81.95 g       water                                                           100.00 g                                                                      ______________________________________                                    

50 g of the above hair coloring agent is mixed with 50 ml hydrogenperoxide 6% aqueous solution shortly before use and the mixture is thenapplied to white human hair. After an acting time of 30 minutes atapproximately 40° C., the hair is rinsed with water and dried. The hairis colored deep blue.

Example 9: Hair coloring agent in cream form

    ______________________________________                                        0.50 g        3,5-diamino-2-tetrafluoroethoxytoluene dihydro-                               chloride produced according to Example 6(a)                     0.20 g         -p-phenylene diamine                                           0.30 g        sodium sulfite, anhydrous                                       3.50 g        lauryl alcohol diglycolethersulfate, sodium salt                              (28% aqueous solution)                                          15.00 g       cetyl alcohol                                                   5.00 g        ammonia, 22% aqueous solution                                   75.50 g       water                                                           100.00 g                                                                      ______________________________________                                    

50 g of this hair coloring agent is mixed with 30 ml hydrogen peroxide6% aqueous solution shortly before use and the mixture is then appliedto blond human hair. After an acting time of 20 minutes at 40° C., thehair is first rinsed with water and then immediately rinsed with adiluted citric acid solution and finally dried. The hair is colored red.

Example 10: Hair coloring agent in gel form

    ______________________________________                                        2.00 g      2,4-bis--[(2'-hydroxylethyl)-amino]--tetrafluoro-                             ethoxybenzene dihydrochloride produced according                              to Example 2                                                      1.30 g      2,5-diaminobenzyl alcohol sulfate                                 0.30 g      ascorbic acid                                                     15.00 g     oleic aoid                                                        7.00 g      isopropanol                                                       10.00 g     ammonia, 22% aqueous solution                                     64.40 g     water                                                             100.00 g                                                                      ______________________________________                                    

Shortly before using, 50 g of this hair coloring agent are mixed with 50ml hydrogen peroxide solution (3% aqueous solution) and the mixture isallowed to act on white human hair for 30 minutes at 40° C. The hair isthen rinsed with water and dried. The hair has obtained an intensiveviolet-blue coloring.

Example 11: Hair coloring agent in gel form

    ______________________________________                                        2.5 g         2,4-diamino-5-tetrafluoroethoxytoluene dihydro-                               chloride produced according to Example 5                        0.5 g         3,5-diamino-2-tetrafluoroethoxytoluene dihydro-                               chloride produced according to Example 6                        4.0 g          -p-toluylene diamine sulfate                                   1.0 g         resorcinol                                                      0.3 g         ascorbic acid                                                   1.0 g         hydroxylethylcellulose, highly viscous                          5.0 g         lauryl alcohol diglycolethersulfate, sodium salt                              (28% aqueous solution)                                          10.0 g        ammonia, 22% aqueous solution                                   75.7 g        water                                                           100.0 g                                                                       ______________________________________                                    

50 g of the above hair coloring agent are mixed with 50 ml hydrogenperoxide 6% aqueous solution shortly before use and the mixture is thenapplied to white human hair. After an acting time of 30 minutes at 40°C., the hair is rinsed with water and dried. The hair is colored black.

Example 12: Hair coloring agent in the form of an aqueous solution

    ______________________________________                                        0.50 g        3,4-diaminotetrafluoroethoxybenzene dihydro-                                  chloride produced according to Example 3                        0.50 g        3-amino-4-(2'-hydroxylethyl)-aminotetra-                                      fluoroethoxybenzene dihydrochloride                                           produced according to Example 4                                 2.00 g         -p-toluylene diamine sulfate                                   0.40 g        resorcinol                                                      10.00 g       ethanol, 96% aqueous solution                                   10.00 g       ammonia, 25% aqueous solution                                   5.00 g        lauryl alcohol diglycolethersulfate, sodium                                   salt (28% aqueous solution)                                     71.60 g       water                                                           100.00 g                                                                      ______________________________________                                    

25 g of the above hair coloring agent are mixed with 25 ml hydrogenperoxide 6% aqueous solution shortly before use and the mixture is thenapplied to white human hair. After an acting time of 45 minutes at 35°C., the hair is rinsed with water and a diluted citric acid solution anddried. The hair is tinted in a natural blond tone.

While only several embodiments and examples of the present inventionhave been shown and described, it is obvious that many changes andmodifications may be made thereunto, without departing from the spiritand scope of the invention.

What is claimed is:
 1. A composition for the oxidative coloring of hair, comprising:a developer component; and at least one coupler component selected from the group consisting of a compound of the formula: ##STR7## wherein, R¹ represents a substituent selected from the group consisting of hydrogen and an alkyl having from 1 to 4 carbon atoms; and R², R³, R⁴ represent the same or different substituents independently selected from the group consisting of hydrogen, an alkyl having from 1 to 4 carbon atoms, a monohydroxyalkyl having from 1 to 4 carbon atoms and a dihydroxyalkyl having from 1 to 4 carbon atoms, provided that the amino groups are situated relative to one another in a positioning selected from the group consisting of ortho- and meta-, and the acid addition salts of said compound.
 2. The composition according to claim 1, wherein the amino groups of said coupler component are arranged in a meta-position relative to one another.
 3. The composition according to claim 1, wherein R¹ of said coupler component is an alkyl having from 1 to 4 carbon atoms.
 4. The composition according to claim 1, wherein R¹, is an alkyl having from 1 to 4 carbon atoms; and R², R³ and R⁴ of said coupler component are independently selected substituents selected from the group consisting of an alkyl having from 1 to 4 carbon atoms and an hydroxyalkyl having from 1 to 4 carbon atoms.
 5. The composition according to claim 4, wherein R¹, is methyl and R², R³ and R⁴ of said coupler component are independently selected substituents selected from the group consisting of methyl and hydroxyethyl.
 6. The composition according to claim 1, wherein said coupler component has at least one of the radicals, R² and R³, as hydroxyethyl.
 7. The composition according to claim 1, wherein said coupler component is at least one member selected from the group consisting of 2,4-diaminotetrafluoroethoxybenzene, 2,4-bis-(2'-hydroxyethyl)-amino-tetrafluoroethoxybenzene, 3,5-diamino-2-tetrafluoroethoxytoluene, 2,4-diamino-5-tetrafluoroethoxytoluene, 3,4-diaminotetrafluoroethoxybenzene and 3-amino-4-(2'-hydroxyethyl)-aminotetrafluoroethoxybenzene.
 8. The composition according to claim 1, wherein said coupler component is 0.01-3.0% by weight of said oxidative hair coloring composition.
 9. The composition according to claim 1, wherein said developer component is at least one member selected from the group consisting of 1,4-diaminobenzene, 2,5-diaminotoluene, 2,5-diaminoanisol, 2,5-diaminobenzyl alcohol, 3-methyl-4-aminophenol and 4-aminophenol. 